The frequency of chirping, F, in crickets (measured in chirps per second) is linearly related to temperature, T, (measured in degrees Fahrenheit). A cricket has a chirping frequency of 10.9 chirps per second when the temperature is 71.5 degrees Fahrenheit and 16 chirps per second when the temperature is 85.9 degrees Fahrenheit.

Express the chirping frequency as a linear function of the temperature. Use the variable in the problem and correct functional notation. Round your final answer to two decimal place.